04 EC300 jetting?

DWreck

New member
Just bought this bike a while back.

Finally pulled the carb to see what I had in there:

Pilot- 40
Air screw - 2 1/2+ turns out
Main- 178
Needle- N1EF clip at the top (leanest)
Slide- 7

I live in Stillwater, OK. Altitude around 900ft.

Bike seems slightly rich. Whenever I get into an opening where I can really get on it it seems as though it takes a minute to clean out and pull hard.

I just put a 35 pilot in it and it seems a little better but this was a quick run up and down the street at temperature near 100 degrees.

Just wondering what works for you guys. Have heard good things about LTR.

Post em up!

Thanks, Derek
 
First off, I am jeff dunham, my best friend is Les Tinius of LTR... (so you know my bias).

From what Les has told me and in talking to other gasgas owners the LTR jetting kit works for most folks There is personal preference about how a bike should run, riding style and in what domain a person wants the bike to run cleanly. So talking about jetting is at times about as productive as discussing politics in a bar.

He told me has sold over 2500 jetting kits worldwide. They are sold through a variety of dealers and also on-line vendors (e.g. www.gofasters.com). If you contact Les (e-mail or phone)- he will set you up with a needle and a set of jets specifically tailored for your bike, altitude and environmental conditions. And yes, it is a needle made by keihin specifically for this carb (numbers machined off to protect the innocent)...

He will also help you dial it in after you receive it. It costs $36 and includes support and consultation with Les to help get things "dialed in" (look here for his qualifications).


I think it might be better to describe my experiences. What Les told me during the process, and what conclusions I drew from it all. This way you can seperate out my experiences from my conclusions and develop your own picture of the situation (and maybe factor in my bias too!). Then you can decide which way you want to go to dial in your jetting.

jeff
 
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FYI - another alternative is the carb mod done by RB-Designs. He inserts divider plates and also does carb boring.

So Ron, what do your customers see when going with this mod? And I notice that you can also bore the carb to 39 at the same time - with the plate in place will going to 39 also work for tight woods stuff? Or do you just recommend it for more open terrain?

I have actually thought of going to a 36mm carb for tight woods - but am now thinking the divider plate might be a better way to go... ???

thanks,
jeff
 
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And, also, it seems to me that RBs method of placing the seperator plate on the intake side of the slide would be alot more effective than placing it on the filter side of the slide. What does everyone else think?

thanks,
jeff
 
Jeff and others,

What the divider plate does, is reduce the size of the carb at the first half of the throttle opening. In effect it is like having a smaller carb which in turn makes the pilot circuitry more sensitive giving better throttle control.

This does give the bike more control at lower throttle settings. Once the slide passes the divider plate the carb just gets bigger and bigger as the throttle opens. This lets you have the same power delivery at WOT as it did before.

Boring a carb will give you better performance on the top end, but will reduce the low end sensitivity.

So a carb mod such as boring and installing the divider plate will give the benefits of a smaller carb on the bottom end and the benefits of a bigger carb on the top end.

Ron
 
Hey guys, thanks for the honest/biased replies. :)

I'm not really trying to make the motor run like something else, just want to clean it up a little.

I will probably see if I can get a couple sizes smaller main jets and see if I can at least get the needle back to the middle of the clip. I'm guessing that if I don't like the way the bike runs after that it will be time to try a different needle.

$36 dollars is pretty reasonable for a jetting kit. I know I could spend that in a hurry if I started experimenting with different needles and considering the lack of knowledge that I have on the subject it would be like throwing darts in the dark.

I think the rb carb mod is what I have read about being popular with KDX owners. Not sure that is the direction I want to go right now. Cool to have the option though.

Thanks again, Derek
 
FWIW, I have an 04 EC300 with the LTR Kit

Here's my experience...

Firt off, Les' service is great. Though I think it's hard to describe what is going on with the bike over the phone so that he can give solid feedback. Sometimes I think I just need to take it to him so he can ride it himself (I'm close enough to actually do that).

My bike wouldn't even run when I got it. It wouldn't idle at all, and even when opened up ran like crap. I put in Les' kit and adjusted the pilot and idle screws per his instructions and I had a running bike. I live in Portland, OR which is essentially sea level with 70 - 90 degrees in the summer.

I had some problems with the bike stalling on down hills. Les recommended adjusting the floats. That seemed to fix the problem.

However, somewhere along the line I changed oils (I went from using Torco to Mobile 1) and started having problems with the bike not wanting to idle clean and needing to be reved out a bit. I've leaned out my fuel mix a bit (I am now running 44:1, I was at 40:1), as I was getting more smoke than I wanted, but still have the idle problem.

I don't notice it when I am riding. The bike responds fine, etc at low and mid throttle settings. Sometimes I feel like it's a little off on top, but I rarely ride there, so can't say for sure.

In any case, whatever I would like to improve isn't bothering me enough to spend the time to mess with it.

I won't say my bike is jetted perfectly, but I think it is close, and Les' kit was a huge improvement over stock.

I'm considering trying the divider plate from RB as it sounds like it may correct my problem. Maybe I can get Ron to give me his impression on my jetting as well (he's even closer :) ). I'm not sure if I want to try that first, or go with the head mod Erik K. raves about.

One or the other is coming up soon. I have some downtime between enduros, so now's my opportunity to get some work down. The Black Bear enduro is in November. It'll be slick NW clay for 50+ miles. I'll need all the throttle control I can get at low speeds. I'm also going to try a trials tire for the first time.

Stay tuned....
 
Magellan said:
The Black Bear enduro is in November. It'll be slick NW clay for 50+ miles. I'll need all the throttle control I can get at low speeds. I'm also going to try a trials tire for the first time.

Stay tuned....

Magellan, not much slick clay this year! Our club has moved this event to Tahuya. This is the same location of the Spark plug Enduro. It will be many miles of tough single track. If its wet, which I would expect it will be, slimy roots and rocks will be the norm and you will still be able to truly test the performance of that trials tire! See ya there, Roscoe
 
There almost seems to be 2 EC300s - one works well with a big pilot and one works well with small. I use a 38 currently and am thinking of trying a 35. Either the N1EF needle or LTR works best on 2nd slot for me. I have 178 main and #7 slide.

There are various theories why there seems to be so many differences on the pilot front, I don't suppose we'll ever be sure. I certainly don't believe it's all rider preference because my bike runs so bad on big pilots no one could like it! The conclusion is the same though - unfortunately you have to jet these bikes individually.
 
I thought I would report back.

I have tried 4 different settings and seem to have found one that makes me happy.

#1 40p 178m N1EF 1st clip - Too rich

#2 35p 178m N1EF 2nd clip- Better off idle, still too rich at mid throttle.

#3 35p 175m N1EF 2nd clip- A little too lean. Bike wanted to rev on it own when hot

#4 38p 175m N1EF 2nd clip- Just about perfect.

It has been pretty warm around here. I may have to richen it up a little for cold weather but right now my air screw is at 1 1/2 out and the bike has good throttle response and pulls smoothly through the rev range.
 
Just an update.

Once it cooled off I went to:

#5 40 p 175m N1EF 2nd clip- a little smokey and felt lean on top on when I was wide open on a grass track.

I just ordered a N1EG and N3EH to play around with. Does anyone have experience with these in the 300?

If I don't end up happy with either of these the LTR kit will be next.
 
Ran with the following setup today:-

35p, 178m, LTR 0 top clip.

The 35 was a definite improvement in the woods. I had a little flat spot while winding on the throttle slowly somewhere about mid throttle. So I will go back to 2nd notch on the clip.
 
My '02 took a lot of patience. (bought new in '05) I have an FMF Gnarly with a T/C silencer. I ended up with a 35 pilot, needle in 2nd position, and a 172 main. I still have a bit of spooge on the end of the silencer, but it doesn't ooze down the body of the silencer like it did before.

Overall, the bike is a little on the fat side, but it beats the alternative. I've had no problems.
 
I have a couple of rides on it now with the N1EG.

42p, N1EG 2nd, 178 main

It starts easier than my previous settings and is smoother from top to bottom. It feels just a tad rich everywhere but very little spooge. I could live with this but for some reason feel inclined to continue looking for perfection.
 
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